Closure device for metallic containers



Nov. 27, 1934. J. w. sHERA GLOSURE DEVICE FOR METALLIC CONTAINERS FiledMay 4, 1932 2 Sheets-Sheet 1 ilnullnmrwww m m m.

Nv.27,1934. 1 w. SHERA 4 1,982,145

CLOSURE DEVICE FOR METALLIC'CONTA-INERS v Filed May 4,4 1932 2sheets-sheet 2 4 55' forming the seal cap;

n Patented Nov. 27, 1934 CLOSURE DEVICE FOR IVIETALLIC CONTAINERS JohnW. Shera, Chicago, lll., assigner to American Flange & ManufacturingCompany, Chicago,

Ill., a corporation of Illinois `App1ication May 4, 1932, serial No.609,093

14 Claims.

My invention relates generally to metallic containers such as drums,barrels, and the like, and it has to do particularly with closure meansfor 'the filling and/or discharge' openings thereof.

My invention is well adapted for use in connection with containersfitted for the transportation and storage of oil, gasoline and the like.

The principal object of my invention is to provide an improved, simpleand inexpensive closure assembly for openings in containers of theforegoing character, which closure assembly is adapted to positivelyseal the container opening against leakage andis of a character whichinsures against undetectable tampering.

Another object is to provide a closure embodying a threaded bushingmember deningthe conf tainer opening land adapted to be closed by a"gasket-carrying plug, the bushing member being provided with anangularly-disposed seat surface above its threaded part adapted to beengaged by the head oi' the plug for limiting the depth of insertion ofthe plug and predetermining the sealing position of the plug and itsgasket.

A further object is to provide an improved and novel seal cap adapted tobe securely mounted over the closure plug to conceal and render thelatter inaccessible, the cap being so constructed and being soassociated with its mounting that it cannot be removed without sodistorting and fracturing the same that its further usefulness isdestroyed.

-An additional, and more specic, object is to provide a seal cap for aclosure opening dened by annular wall structure projecting outwardlyfrom the container wall, which cap has a smooth skirt portion of-suflicient length .to extend, when secured in place, into closeproximity to the container wall thereby preventing detachment orloosening o f the same by insertion o f an object,

under the free edge of its skirt, such cap being cross-scored throughits top a'nd skirt to permit of removal of the same by fracturing andtearing away the scored portion.

Other objects and advantages will become apparent as this descriptionprogresses and by reference to the drawings wherein,

Figure 1 is a vertical sectional view o f one form of closure assemblyembodying my invention;

Fig. 2 is an elevational view, partially in section, of the closure,illustrating the position of the seal vcap thereon prior to itssecurement; Fig. 3 is a separated plan view of the plug and gasketassembly shown in Fig. 2; Fig. 4 is a plan view of one form. of blankfor (Cl. 22o-39) Fig. 5 is a bottom plan view of a seal cap formed fromthe blank of Fig. 4;

Fig. 6 is a perspective view of a modied form of cap embodying myinvention;

Fig. l is a plan view of anothermodied form of a cap blank embodying -myinvention; and

Fig. 8 is a perspective view of a cap formed from the blank of Fig.

Referring particularly to the structure shown in Figs. 1 to 5,inclusive, the container wall 10 is 65 provided with a circular openingdeiined by an outwardly-projecting, annular flange 11 struck,preferably, from the metal of the container wall. The wall surface atthe base of the flange 11 is struck outwardly providing an annular boss12 70 forming a pocket 13 adapted to receive the horizontal flange 14 ofan internally threaded bushing 15, the body 15a of which is adapted to tsnugly within the flange 11. The pocket 13 and bushing flange 14 are,preferably (but not neces- 75 sarily), of octagonal shape in outline forpreventing rotation of the bushing 15 within the ilange 11. To securelylx the bushing 15 to the ange 11 against-axial displacement, the upperedge of the bushing above its threads 15b is gradually 80 thinned and isextended upwardly and rolled over the outer edge of the flange 11forming a bead 17 thereat. Any suitable sealing member or com pound 18may be inserted between the top wall of the pocket 13 and the bushingaange 14 and, 85 with the parts secured as just described, a leakproofjoint is provided as between the bushing 14, the container wall and theange 11. 'I'he bead 17 provides at the outer edge of the containeropening a rounded, angular seat above the bushing thread which isutilized in a manner which will be described more fully hereinafter.

The bushing opening is adapted to be closed by a metallic plug 19 whichmay be formed of any suitable material and in any desired manner to 95the shape best shown in Figs. 1 and 3. Specically, this plug is providedwith a cup-shapedbody 19 (Fig. 3) having its lower portion threaded forengagement with the bushing threads 15b, and it is further provided witha head 19b of slightly 100 larger diameter than the diameter of itsthreaded body portion. The surface 19c between the plug -head 19b andthe threaded plug body serves to support a gasket 2 0 formed from anysuitable material, such as rubber, ber, etc., with'an outside 105diameter approximately the same as the diameter of the plug head 19h.'Ihis gasket, as will be seen hereinafter, seals the threaded connectionbetween the bushing 15and plug 19. The bottom portion of the surface 19cadjacent the plug no threads is approximately the same depth as the plugthreads but the upper portion of the same is roundedl and is slightlydeeper than the plug threads providing a well defined groove in whichthe gasket is retained'and compressed when the plug is screwed intoclosure position. Insertion and removal of the plug is facilitated by apair of opposed lugs 19d projecting inwardly from the inner wall of theplug body (Fig. 1).

I have found that, in closure devices of the foregoing character, unlessguarded against, the plug may (due to lack of proper care and skill) bescrewed into the bushing beyond its desired sealing position with theresult that the gasket is forced into the bushing and plug threadthereby cutting and distorting the same in such a way that the desiredsealing effect is destroyed. If such a condition should exist, theusefulness of the gasket is destroyed and a new gasket must besubstituted, otherwise the proper seal cannot be effected. To guardagainst the foregoing, and to insure (in a fool-proof manner) that theplug will always be moved to a proper andpredetermined sealing position,I relate the plug head 19h, bead seat surface 17e, gasket groove 19, andthe threaded connection between the plug 19 and bushing 15 in such a waythat the extent to which the plug may be screwed into the bushing islimited-to that predetermined position. wherein the gasket effects thedesired positive seal against the threaded connection between thebushing and plug 19. Specifically, the width ofthe plug head 19b is suchthat its bottom edge strikes the irmer rounded bead seat surface 17(Fig. 1) slightly below the top of the bead, and the plug groove 19c andgasket 20 are of such relative size that as the plug head reaches theforegoing position the gasket is fully compressed and sealed upon thebushing and plug threads forming a tight seal. Furthermore, due to thehead engaging the inner rounded (downwardly and inwardly inclined) seatsurface of the bead, the engagement thus effected provides awedging-like action which further insures the tightness of the seal andaids in prevention of loosening of the plug due to vibration, shock andother causes. I

To complete the closure assembly, I employ a seal cap 21 (Figs. 1 and 2)which seats over the plug 19 with its skirt portion 21*l contractedaround and behind the bead 17 and extending down along the flange 11-thereby concealing the plug 19 and rendering the same inaccessible. Itis highly desirable that this seal be so constructed and applied that,once applied, it cannot be removedV and/or reapplied without detection.To this end, I provide a cap ,which cannot be removed without fracturewhich destroys its further usefulness. The cap can only be removed bytearing away scored sections-andV the cap skirt is so related to itssupporting structure that it cannot be pried or forced outwardly fromthe closure structure by the insertion of an object under the free edgeof its skirt. Specifically, the top of cap 21 is slightly raised so asto seat upon the plug 19.

' and its outer peripheral edge portion is slightly depressed as at 21bdefining a surface which supports a gasket 22 of any suitable material.This gasket has, normally, an inside diameter approximating the outsidevdiameter of the plug head'19b so that it will fit freely around theedge of the plug head and upon the top of the bead 17. The cap skirt 21*is of suchV length that when the cap is secured in place, its free edgeextends into such close proximity to the surface of the boss 12 that itwould be practically impossible for a person to project an objectbeneath such edge capable of prying loose the cap 21. Protection in thisrespect is further given by forming the cap skirt with asmooth surface,so that when it is secured in place it fits snugly around the flange 11and there are no projecting parts or` surfaces which may be engaged byan object for the purpose above mentioned.

T'he cap 21,'before being secured to the closure, may take the form bestshown in Figs. 2 and 5. It will be 4noted in Fig. 2 that the cap whenassembled upon the closure before securement is in a somewhat raisedposition due mainly to the thickness of the gasket 22 which iscompressed during the cap-securing operation. The cap is, preferably,secured by means of a tool of the character disclosed in the copendingapplication of Fleck W. Sample, Serial No. 573,695. In the applicationof the cap by the tool just stated, the cap skirt is rst moved radiallyinward against the outer' rounded bead surface which translates the capskirt movement into axial movement so that the cap skirt is contracteduniformly behind the bead 17 and into snug-fit engagement with theflange l1 throughout its circumference, as best shown in Fig. 1. Duringthis cap-securing operation, the gasket 22 is compressed upon the top ofthe bead, the top of the cap is seated upon the plug v19 and aleak-proof joint is provided as between the cap and the bead 17.

By securing the cap in the foregoing manner it is so firmly fixed inplace that special provision must be made for detachment of the same bythe user. To that end, I may provide the top of the cap and its skirtwith scored sections 23 and 24 (Figs. 4 and 5). The cap is formed from aflat blank (Fig. 4) which is provided with score lines 23* and 24a whichare continuous to the edge of the blank except for skip portions 2liband 24h, the purpose of which will be explained hereinafter. When thecap is fully formed (Fig. 5), the skip portions 23b and 24b lie in thedepressed peripheral portion 21h of the cap top and immediately abovethe gasket 22. These skip portions insure a uniform depression of thegasket 22b when the cap is applied, thereby effecting a uniform sealaround the top of the bead. To remove this particular form of cap in anauthorized manner, it is only necessary to break through the scoredcenter of the cap and tear away some or all of the scored sections, thetear being continuous down through the fr ee edge of the skirt,` therelatively small skip portions 23h and 24b not interfering with this. Ihave found that a cap .formed in the foregoing manner may be made fromrelatively'heavy gauge sheet metal which further aids in the sureness ofthe seal and reduces the possibility of tampering with theclosure.

'Ihe scoring of the cap top may be varied. For

example, it may take the form shown in Fig. 6'

wherein only one scored section 25 is employed, which section isidentical to the section 23 or 24 of Fig. 5. I may also employ a capscored similarly to that oi! Fig. 6 except that it is further providedwith a plurality of radial score lines 27 in its skirt portion 28. Sucha cap and its blank are shown in Figs. 7 and 8. The purpose of theseskirt scores is to further guard against undeto detach the cap, the capskirt would tear said flange along the scored lines 27 without detachingthe cap and it would clearly show tampering. Furthermore, if the capshould be tampered with in this manner, and the. skirt portion torn, thefurther usefulness of the cap is destroyed.

From the foregoing, the objects and advantages of my inventionhereinabove Ilrst stated will be obvious. A fool-proof, properly sealedclosure is insured., Undetectabletampering is guarded against. It willbe understood that while I have shown and described only two forms of myinvention, other changes in details and arrangement of parts maybe madewithout departing from the spirit and scope of my invention as denel bythe claims which follow.

I claim:

l. In structure of the class described, means providing an opening in awall of the container,

the lower or inner part of which opening is threaded and the outer partof which opening is provided vm'th an unthreaded seat taperingdownwardly and inwardly from the outer edge of said opening to the topof its threaded part, a closure plug having a threaded body part adaptedto engage said threaded opening and having a head of greater diameterthan its threaded body part and of less diameter than the outer part ofsaid opening and adapted to engage the tapered surface of said seatsomewhat above the threaded part of said opening to limit the depth ofinsertion of the plug in said opening, and a readily compressible gasketcarried by said plug between its head and threaded body part and adaptedto be compressed against said seat below the point of engagement betweensaid seat and plug head and above the threads of said opening.

2. In structure of the class described, means providing an opening inthe Wall of the container, the lower part of the wall of said openingbeing v threaded and its upper part above said threads` taperinguniformly outwardly from said threads, a plug having a threaded bodyadapted to engage said opening threads. and a head of less diameter thanthe outer portion of said upper tapered part and adapted to seat againstsaid tapered opening wall above said threaded part, said plug alsohaving an annular groove between its threads and head of a depth equalat least to the depth of said threads, and a gasket normally ofsubstantially the same diameter as said head mounted in said groove;

3. In structure of the class described, means including an annularflange projecting outwardly at substantially right angles from a wall ofthe container forming an opening therein, a bead formed at the outer endof said ange, a plug mounted in said opening, and a cap member mountedover said plug and opening-forming means with its skirt portioncontracted uniformly around and over said bead and with its free edgeportion extending inwardly from said bead along in substantiallyparallel relation throughout to the latter, said skirt being ofsufficient llength to permit the same to, be contracted overand behindsaid bead into snug ilt engagement with said ange and to project itsfree edge vertically into close proximity to said container wall at thebase of said flange to pre-A vent access to said free edge fordetachment of the cap', and a gasket carried by said cap and seated uponsaid bead and adapted to be compressed upon said bead as said cap issecured in place by contracting the skirt behind said bead.

4. In structure of the class'described, means fincluding an annular angeprojecting outwardly Acap is secured in place.

container to form an opening in the latter. a bead upon and surroundingthe outer end of said ange, a plug in said opening and having a head,and a cap member mounted over said plug and opening-forming means withits skirt portion extending inwardly towards said container wall oversaid bead and along said ange in substan tially parallel relationthroughout to the latter,

lsaid skirt having a portion contracted uniformlyV and snugly over saidbead, and said skirt being of suflicient length that after it has thusbeen contracted over said bead it extends. behind said bead and iscontracted into snug nt engagement with said ange with its free edgeextended ver-l tically into close proximity to said container lWall atthe base of said i'lange thereby preventing access to saidfree edge fordetachment of the cap, and a gasket carried by said cap and surroundingsaid plug head and seated upon saidr bead, the same being adapted to bevcompressed upon said bead and to be confined in compressed relationbetween said cap skirt and said plug head as said cap is secured inplace by contracting the skirt thereof over, upon and behind said bead.

5.\In structure of the class described, -means forming an opening in awall of the container which includes an outwarly extending annularflange and a bushing surrounded by said flange and turned upon thelatter to provide a bead at the outer end of said flange, a plug mountedin said opening and having a head adapted to project somewhat above saidbead and surrounded by the latter, a cap adapted to be mounted overrsaid plug and bead and having a smooth skirt wall normally of greaterdiameter than said bead and flange and of sufficient length whencontracted-over and upon said bead and said iiange to extend its freeedge to the wall of the'container at the base of said flange, said caphaving the outer periphery of its top depressed somewhat below theperiphery of said plug head, and a gasket supported by the depressedportion of said c ap top and adapted to be compressed upon said beadbetween said plug head and cap 6. In structure of the class described,an annular flange extending from a wall of the container and providingan opening, means forming a bead at the outer end of said flange, a plugclosing said opening, a cap adapted to be mounted over said flange, beadand plug with its skirt portion uniformly contracted behind said bead insnug iit engagement with said flange and with the free edge of its skirtportion extending substantially into engagement with the wall of thecontainer, a ring gasket between said bead and the top of the cap, saidcap having a scored section extending across its top and down throughits skirtv on opposite sides and adapted to be detached for removal ofthe cap, the scoring of said section lbeing interrupted at the peripheryof the cap top immediately above said gasket.

7. In structure of the class described, means forming an Opening in awall of the container with an exterior bead therearound, a plug mountedin saidopening, and a cap adapted to be mounted over said plug and beadwith its skirtv is n ing threads and a gasket-receiving groove imme--vided with internal threads extending from its inner end andterminating short of` its outer end with the outermost side of theoutermost thread merging into the interior unthreaded wall of thebushing therebeyond to form a gasket seat -which is uniformly flaredoutwardly, a plug having a head of less widthy than the outermostdiameter of said gasket seat, said plug also having a threaded body partin engagement with said bushdi'ately beneath said head, and a gasket ofresilient material supported in said groove, said gasket being of suchdimensions that it does not project laterally beyond said head, and uponscrewing said head fully into said bushing the gasket is seated upon theouter side of the outermost of said threads and is compressed againstand confined between said outermost thread, said head, said groove andthe'inner wall of said bushing outwardly beyond said outermost thread,and said plug head is, at the same time. so related to said gasket seatthat it is engaged with said seat inwardly of the outer end of thelatter.

9. In structure of the class described, means forming an opening in thewall of a container which includes an outwardly extending' annularflange, means at the outer end of said flange forming a bead therearound, a plug mounted in said opening and having a head adapted to liewithin the confines of said bead being surrounded by the latter, a capadapted to be mounted over said plug and bead and having the smoothskirt wall normally of greater diameter than said bead and flange and ofsufficient length when contractedv over and upon said bead and flange toextend its free edge to the wall of the container at the base of theflange in substantially right angle relation with respect thereto, saidc ap having the outer periphery of its top offset somewhat with respectto said plug head, and a gasket supported by the offset portion of saidcap top and adapted to be compressed upon said bead at a point betweensaid plug head and cap skirt wall as said cap is secured in place.

,10. A seal cap for structure of the class described which comprises asmooth top and a smooth skirt both of whichare imperforate, and aplurality of equally and i circumferentially spaced score lines in saidskirt and extending throughout the length'of the latter whereby pressureapplied at any point to the free edge of said skirt and axially of thecap will tend to fracture only the skirt without freeing the cap for removal.

11. A seal cap for structure of the class described which comprises atop and a skirt portion bothof which are imperforate, an offset portionaroundthe periphery of said top portion defining a distinct andcomparatively narrow gasket-supn porting surface, a scoredsection in andextending across said top portion with its opposite ends terminating atsaid gasket-supporting surface, and scored sections in and extendingfrom the free edge of said skirt portion adjacent the opposite ends ofsaid topscored section, said skirt scored sections being aligned withsaid top scored section and terminating at said gasketsupportingsurface.

l2. A seal cap for structure of the class described which comprises atopand a skirt portion, both of which are imperforate, a comparativelynarrow offset gasket-supporting surface around the periphery of said topportion, a plurality of scored vsections in and extending across saidtop portionat an angle to and intersecting each other, and scoredsections in and extending of scored sections in said skirt portion allterminating at said gasket-supporting surface, and at least one of saidskirt scored sections beingaligned with said top scored section.

14. A seal cap for structure'of the class de-` scribed which comprises asmooth top and a smooth skirt, both of which are imperforate, said tophaving a definitely defined and compartively narrow gasket-receivingsurface formed around its periphery, a scored section extendingtransversely across said` top and terminating at but not passing throughsaid gasket-receiving surface, a plurality of scored sections throughthe circumference of said skirt extending throughout the length of saidskirt and terminating at said gasket-receiving surface, some of whichlatter sections are in alignment with said top scored section.

JOHN W. SHERA.

